Microphone cable differences

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Brian May uses a set-up that could be deemed as absurd in pure technical terms.
His Red Special originally incorporated a Vox Treble Booster.
Actually, due to its quite low input impedance, combined with the pick-ups inductance the TB starts with a serious band-pass filter that attenuates both treble and bass, and leaves only the midrangey sound.
When BM found out he got a better sound without the TB and just the natural distortion from the AC30's, he noticed that long cables actually moved the bandpss a few notches down, to a sound he liked more.
Such a set-up cannot be qualified in the usual terms of fidelity, like frequency response or distortion.
 
Hendrix also liked the curly cables because he could use it to make the guitar wail when he used feedback from speaker to pickup , downside is it can sometimes form a tuned circuit that demodulates radio transmissions ,
At the Isle of Wight 1970 concert Hendrix is all bummed out about the amps , Rory Gallaghers Taste also had major problems with breakthrough from police radio and brown outs of the mains supply at that festival .

Of course were in a very different place now with regards RF interference than we were back then , noxious levels of it are everywhere . I think the effect of using curly cables now would be so unpredictable that it would cause headaches .

I never thought of measuring a curly cable with the LCR , chances are both inductance and capacitance vary as the cable is stretched .
 
I believe it was the Dallas Rangemaster top boost pedal Rory recomended to Brian and it became an integral part of his sound.

Straight from the horses mouth , as we say
 
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And throw in that a typical passive electric guitar pickup also sees a variable impedance due to a tone control circuit.
A late reply but, as someone who does a LOT of amps every month I’ve never seen a guitar amp ever where signal hits a tone stack before anything else.

Post 1940’s virtually every decent commercial guitar amp built has the same input configuration- a 1M or higher load resistor to ground right at the jack, and a 68k (or so) grid stopper to the first tube stage. On some cheap/dept store brand small amps I have occasionally seen the input hit the volume pot first, but it’s still using the pot to ground as the terminating impedance.
 
I once recorded a guitar player. He said he preferred a short cable, because with long cables he could hear the delay. :D
I said: even if you would use 100 meters, you won't hear a delay! (The audio quality may suffer, especially on a guitar element, but certaily there is no delay!)
Well, he just clearly had MUCH better hearing than you, that's all.

Don't let it get you down; "...for always there will greater and lesser persons than yourself." 🙏
 
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The different brands of mic cable sometimes age differently after a few years of handling and coiling. May be then it makes an audible difference.
 
The different brands of mic cable sometimes age differently after a few years of handling and coiling. May be then it makes an audible difference.
I have to say that I have never noticed any difference in a mic cable at studio lengths, as long as it wasn't broken - and I have some here I made in 1974 (I made them carefully, with decent cable, pre oxygen-free, and early adhesive-backed heatshrink - I have never had to fix them). But on tour and in theatre and with much greater lengths I have noticed differences and prefer decent double sheathed star-quad, for the noise-rejection, not the audio quality.
 
guitar player ... preferred a short cable, because with long cables he could hear the delay.

I remember using coiled cables way back in 1968 because they were considered "cool." - But, we quickly opted for long straight coils for OTHER reasons than audio quality. We soon discovered short, coiled cables were stiff and easily pulled our amplifiers over! It is a real embarrassment when your amp suddenly keels over as you jump around like Pete Townsend or Chuck Barry. Man, I really hate that awful crashing sound of the spring reverb thrashing about. Yep, LONG straight cables are definitely the way to go! :) // James //
 
I remember using coiled cables way back in 1968 because they were considered "cool." - But, we quickly opted for long straight coils for OTHER reasons than audio quality. We soon discovered short, coiled cables were stiff and easily pulled our amplifiers over! It is a real embarrassment when your amp suddenly keels over as you jump around like Pete Townsend or Chuck Barry. Man, I really hate that awful crashing sound of the spring reverb thrashing about. Yep, LONG straight cables are definitely the way to go! :) // James //
My AT headphone came with the option of staraight or coiled cable; I've never used the coiled for a similar reason - pulling stuff off the workbench.
 
I had to buy a mic cable recently. I needed one with a right angle female XLR connector because, the way I have the mic set up, I kept hitting the straight connector and it was getting on my nerves.

It was oddly hard to find XLR cables with right angle connectors. I found a company that makes cables to order. I'm disinterested in cables but I'm also a little neurotic and I don't want a cable that might degrade the sound. So I read that Klaus Heyne said GAC-3 is good.

So I had the company make me a GAC-3 cable with a right angle female Neutrik gold connector on one end and a straight connector on the other. It cost something like $30 or $40. It's a short cable, but a 20 footer I think was only $50.

Anyway. That's the answer. GAC-3.
 
I once recorded a guitar player. He said he preferred a short cable, because with long cables he could hear the delay. :D
I said: even if you would use 100 meters, you won't hear a delay! (The audio quality may suffer, especially on a guitar element, but certaily there is no delay!)
The main problem with connecting electric guitars is the influence of the resonance peak of the pickups by complex loads. Some authors have developed the relevant basic principles: e.g.: Dipl.-Phys. Eberhard Meinl: Elektrogitarren VEB Verlag Technik Berlin 1987 and Helmut Lemme. It would therefore be good if the complex load were very low. So cables should be as short as possible.

Microphone cables: Ing. Wuttke (Schoeps) gave a talk on this at a sound engineers' conference years ago. The output circuit and the output resistance of the microphone are of considerable importance for the influence of the complex load on the subsequent cable. The best way here in my view: put the microphone preamplifier as close to the microphone as possible in order to minimize the complex load.

Best regards!
 
The main problem with connecting electric guitars is the influence of the resonance peak of the pickups by complex loads. Some authors have developed the relevant basic principles: e.g.: Dipl.-Phys. Eberhard Meinl: Elektrogitarren VEB Verlag Technik Berlin 1987 and Helmut Lemme. It would therefore be good if the complex load were very low. So cables should be as short as possible.
That would be so if the goal was to achieve the best HF response, however it's not the case. There have been many attempts to increase the HF respnose of the electric guitar, in a holistic way, i.e. considering all elements of the chain, the pick-ups, the cable and the amp.
For a start, for a reason that maybe both physiological and acquired taste, frequencies above 4-5kHz are not welcome. Typically, most guitar amps use a 10 or 12" loudspeaker which resricts the HF response. Guitar amps with tweeters have been known to exist, and were never popular, often considered too shrill.
Pick-up designers have come with low-impedance designs that could potentially shift the characteristic frequency of the pick-up/cable combo. In the lata 60's, Les Paul did that in his guitars and Gibson incorporated these designs in four models, that were a commercial failure. Their current value is only historical, not playability.
A very easy experiment can be done by connecting an electric guitar to a typical stereo, or to an electroacoustic guitar amp, which has a much extended HF response.
A look at amp simulators (boxes that allow connecting an electric guitar to a standard PA) shows that they all include a low pas filter at about 4-5 kHz, in addition o whatever EQ and processing.
Guitarists that swith from cable to RF transmitter almost always need some time to accomodate the increased HF content reaching their amp(s), because of much lower capacitive load of te short cable from guitar to transmitter.
Many transmitters include a "cable simulator", in the guise of a switch that selects different values of input capacitors.

Microphone cables: Ing. Wuttke (Schoeps) gave a talk on this at a sound engineers' conference years ago. The output circuit and the output resistance of the microphone are of considerable importance for the influence of the complex load on the subsequent cable. The best way here in my view: put the microphone preamplifier as close to the microphone as possible in order to minimize the complex load.
I'm not sure the answer is as clear cut as it, considering there are two actions at work.
One is the capacitive effect, the other is interference noise.
Regarding capacitive effects, you have a low-pass filter constituted of the microphone impedance and the capacitance of cable C1 of length L1, and an other constituted of the preamp's output impedance and the capacitance of cable C2 of length L2.
If the output impedance of the preamp was identical to the microphone impedance, the best location for the preamp would be at mid-distance, with L1=L2.
In practice, the optimum depends on the relative value of the microphone and preamp output impedance.
For example, Schoeps microphone has a rated impedance of 42 ohms, which is likely to be less than the typical impedance of most preamps (50-100 ohms).
In that case, and considering only the HF response, the best choice would be to put the preamp at the other end of the cable.

The other factor to consider is global noise.
It depends very much on how much noise is induced in the cable, but in many cases, elevating the signal by placing the preamp close to the mic will be enough to increase the global S/N ratio.
It's clear that the choice must be balanced with other factors, such as availabilty of power and distant gain control possibilities.
 
For example, Schoeps microphone has a rated impedance of 42 ohms, which is likely to be less than the typical impedance of most preamps (50-100 ohms).
Sorry for my english.
I´m not a native speaker.

In audio, voltage matching is the main method of working. This means Rin >> Rout (rule of thumb factor 10). Most preamps work with input impedances of greater than or equal to 1 KOhm. In the Anglo-American world, power matching is sometimes used. So output resistance = input resistance.
The main problem is the interaction of the complex load with the individual factors. This is discussed in detail in the books on communications engineering. If I find Ing. Wuttke's contribution in the conference documents, I will post the lecture.
Best regards!
 
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